tif@cpe.UUCP (09/17/88)
Written 1:30 am Sep 16, 1988 by viper.UUCP!dave in cpe:sci.space.shuttle >In article <118@avatar.UUCP> kory@avatar.UUCP (Kory Hamzeh) writes: > >Two questions about the space shuttle: > > > > 1. What is the purpose of the roll maneuver at 7 sec after > > lift off? > >There are several reasons for this. Among them are: > 1) To prevent the radio downlink from being blocked by the > fuel tank. > 2) To allow the pilot to be able to see the horizon in case > he has to take over manually. (I thought it sounded like a silly question till I realized I didn't know the answer :-) Is there some obvious-to-everyone-but-me reason that the whole launch pad couldn't be oriented 90 (or whatever) degrees differently so that the shuttle could be in the same flight position without the roll? Paul Chamberlain Computer Product Engineering, Tandy Corp. {convex,killer}!ninja!cpe!tif
henry@utzoo.uucp (Henry Spencer) (09/19/88)
In article <6400003@cpe> tif@cpe.UUCP writes: >Is there some obvious-to-everyone-but-me reason that the whole launch >pad couldn't be oriented 90 (or whatever) degrees differently so that >the shuttle could be in the same flight position without the roll? Had the pad been built for the shuttle, the matter probably would have been attended to. The pad, however, was built for the US's best launch vehicle, the Saturn V. At the time it was designed and constructed, the pad was meant to be used for Saturns well into the 1980s. The notion that Saturn launch capability would be abandoned within a decade would have been considered ridiculous. Even less credibility would have been given to the suggestion that the pads be designed to accommodate an inferior follow-on system. (There *was* some effort made to allow for *better* followons.) -- NASA is into artificial | Henry Spencer at U of Toronto Zoology stupidity. - Jerry Pournelle | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
nak@cbnews.ATT.COM (Neil A. Kirby) (09/19/88)
In article <6400003@cpe> tif@cpe.UUCP writes: > [some people explain well about the roll maneuver ] >(I thought it sounded like a silly question till I realized I >didn't know the answer :-) > >Is there some obvious-to-everyone-but-me reason that the whole launch >pad couldn't be oriented 90 (or whatever) degrees differently so that >the shuttle could be in the same flight position without the roll? A visiting astronaught explained it this way: "That roll move is to do in software what we can't do in hardware. With the early funding cuts in the 70's, NASA couldn't afford extensive mods to pad 39B." The orientation or whatever was set for Saturn launches, not shuttle launches, and they didn't have the $$$ to change it. Neil Kirby ...cbsck!nak
eugene@eos.UUCP (Eugene Miya) (09/20/88)
>Had the pad been built for the shuttle, the matter probably would have >been attended to. The pad, however, was built for the US's best launch >vehicle, the Saturn V. At the time it was designed and constructed, the >pad was meant to be used for Saturns well into the 1980s. The notion >that Saturn launch capability would be abandoned within a decade would >have been considered ridiculous. Even less credibility would have been >given to the suggestion that the pads be designed to accommodate an >inferior follow-on system. (There *was* some effort made to allow for >*better* followons.) There is a facilities problem acknoledged within the Agency when it comes to things like this. Our engineers and scientists create facilities to solve the problem at hand, rarely thinking about the next problem. Such is the case with JPL's IPL (Image Processing Lab) which was a remant of the Viking Program. Do not think image processing is standard operating procedure, it's regarded as a somewhat costly addition. Anyway, for years the Lab sought to upgrade the IPL, now called the Multi-Mission IPL. It's a computer facility independent from the main JPL computer facility (a source of attack), from the researchers who even benefit in the long run (also attack it, where do you think budgets get cut first?). This case is not unique, practically every project in the Agency has a degree of this. As a result it is called the "Project" mentality (we have a definitive start and end date), this contrasts to ongoing "Programs." All I can say is people are aware and some want to change and remember that some degree of change will result in more bureaucracy. So now we have to balance. Another gross generalization from --eugene miya, NASA Ames Research Center, eugene@aurora.arc.nasa.gov resident cynic at the Rock of Ages Home for Retired Hackers: "Mailers?! HA!", "If my mail does not reach you, please accept my apology." {uunet,hplabs,ncar,decwrl,allegra,tektronix}!ames!aurora!eugene "Send mail, avoid follow-ups. If enough, I'll summarize."
karn@thumper.bellcore.com (Phil R. Karn) (09/20/88)
The ability of this group to drum up non-existent problems and then beat them to death with Rube Goldberg solutions never ceases to amaze me. Roll maneuvers are done all the time with both manned and unmanned launchers, and they are absolutely trivial to perform. Recall that in the case of the Shuttle, the degree to which it rolls after liftoff depends on the launch azimuth (which depends on the orbital inclination). If you did the orientation before liftoff you'd need a rotatable launch platform! Geez. This discussion reminds me of the Golgafrincham B-ark gang's solution to their problem of currency inflation... :-) Phil
dave@viper.Lynx.MN.Org (David Messer) (09/20/88)
In article <1226@cbnews.ATT.COM> nak@cbnews.ATT.COM (Neil A. Kirby) writes: >In article <6400003@cpe> tif@cpe.UUCP writes: >> > >[some people explain well about the roll maneuver ] > >>(I thought it sounded like a silly question till I realized I >>didn't know the answer :-) >> >>Is there some obvious-to-everyone-but-me reason that the whole launch >>pad couldn't be oriented 90 (or whatever) degrees differently so that >>the shuttle could be in the same flight position without the roll? > >A visiting astronaught explained it this way: >"That roll move is to do in software what we can't do in hardware. With >the early funding cuts in the 70's, NASA couldn't afford extensive mods to >pad 39B." > >The orientation or whatever was set for Saturn launches, not shuttle >launches, and they didn't have the $$$ to change it. However, the Saturn launches also had a roll maneuver. I think the roll depends on the exact launch azimith and varies from launch to launch. -- If you can't convince | David Messer - (dave@Lynx.MN.Org) them, confuse them. | Lynx Data Systems -- Harry S Truman | | amdahl --!bungia!viper!dave | hpda / Copyright 1988 David Messer -- All Rights Reserved This work may be freely copied. Any restrictions on redistribution of this work are prohibited.
ham@hpsmtc1.HP.COM (Bob Hamilton) (09/21/88)
> The ability of this group to drum up non-existent problems and then beat > them to death with Rube Goldberg solutions never ceases to amaze me. Roll > maneuvers are done all the time with both manned and unmanned launchers, > and they are absolutely trivial to perform. > > Recall that in the case of the Shuttle, the degree to which it rolls after > liftoff depends on the launch azimuth (which depends on the orbital > inclination). If you did the orientation before liftoff you'd need a > rotatable launch platform! YES. I remember when I was growing up (as was Space Science), there was much noise in the literature about how one would have to mount the docking structure of a rotating doughnut type space station on bearings so that it could be driven to zero roation so that shuttles could dock... considerable speculation on the best way to do this. Then came the movie 2001 - Solution: Align shuttle with axis of space station roation. Roll shuttle in sync. with station. Dock. Oh. Yeah. (Why didn't I think of that?) > Geez. This discussion reminds me of the Golgafrincham B-ark gang's > solution to their problem of currency inflation... :-) > > Phil OK. I'll bite. --Bob (Pre- V-2) Hamilton
henry@utzoo.uucp (Henry Spencer) (09/21/88)
In article <1330@thumper.bellcore.com> karn@thumper.bellcore.com (Phil R. Karn) writes: >Recall that in the case of the Shuttle, the degree to which it rolls after >liftoff depends on the launch azimuth (which depends on the orbital >inclination). If you did the orientation before liftoff you'd need a >rotatable launch platform! Why not? That's what the Chinese do for Long March. What's more, the rotation is done by a couple of husky soldiers turning cranks! (Although the overall image is slightly spoiled by the laser measuring widget used by the engineer who gives them orders.) It launches things just fine... "Roll maneuvers? We don't need no steenking roll maneuvers!" :-) :-) -- NASA is into artificial | Henry Spencer at U of Toronto Zoology stupidity. - Jerry Pournelle | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
mcd@iconsys.UUCP (Mark Dakins) (09/24/88)
In article <6400003@cpe> tif@cpe.UUCP writes: | |Written 1:30 am Sep 16, 1988 by viper.UUCP!dave in cpe:sci.space.shuttle ||In article <118@avatar.UUCP> kory@avatar.UUCP (Kory Hamzeh) writes: || |Two questions about the space shuttle: || | || | 1. What is the purpose of the roll maneuver at 7 sec after || | lift off? | |Is there some obvious-to-everyone-but-me reason that the whole launch |pad couldn't be oriented 90 (or whatever) degrees differently so that |the shuttle could be in the same flight position without the roll? | | Paul Chamberlain | Computer Product Engineering, Tandy Corp. | {convex,killer}!ninja!cpe!tif Well, I don't know if it is obvious to everyone but you or not (that is why I am posting rather than mailing). The reason is that the shuttle launch pads are reincarnated Saturn V launch pads. The gantries, rails, vehicle transporters, etc already existed. It was decided to launch in the "wrong" attitude and perform the roll. The alternative would have been to build new launch pads from the ground up and this would have been expensive and time consuming for not much return. -- Mark Dakins, Icon International uplherc!nrc-ut!iconsys!mcd@utah.cs.edu 774 South 400 East, Orem, UT.